
package com.fly.util;

import java.awt.Image;
import java.awt.Rectangle;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;

import javax.imageio.ImageIO;
import javax.imageio.ImageReadParam;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;

public class ImageUtil
{
  /*
   * 根据尺寸图片居中裁剪
   */
  public static void cutCenterImage(String src, String dest, int w, int h)
      throws IOException
  {
    Iterator iterator = ImageIO.getImageReadersByFormatName("jpg");
    ImageReader reader = (ImageReader) iterator.next();
    InputStream in = new FileInputStream(src);
    ImageInputStream iis = ImageIO.createImageInputStream(in);
    reader.setInput(iis, true);
    ImageReadParam param = reader.getDefaultReadParam();
    int imageIndex = 0;
    Rectangle rect = new Rectangle((reader.getWidth(imageIndex) - w) / 2,
        (reader.getHeight(imageIndex) - h) / 2, w, h);
    param.setSourceRegion(rect);
    BufferedImage bi = reader.read(0, param);
    ImageIO.write(bi, "jpg", new File(dest));

  }

  /*
   * 图片裁剪二分之一
   */
  public static void cutHalfImage(String src, String dest) throws IOException
  {
    Iterator iterator = ImageIO.getImageReadersByFormatName("jpg");
    ImageReader reader = (ImageReader) iterator.next();
    InputStream in = new FileInputStream(src);
    ImageInputStream iis = ImageIO.createImageInputStream(in);
    reader.setInput(iis, true);
    ImageReadParam param = reader.getDefaultReadParam();
    int imageIndex = 0;
    int width = reader.getWidth(imageIndex) / 2;
    int height = reader.getHeight(imageIndex) / 2;
    Rectangle rect = new Rectangle(width / 2, height / 2, width, height);
    param.setSourceRegion(rect);
    BufferedImage bi = reader.read(0, param);
    ImageIO.write(bi, "jpg", new File(dest));
  }

  /*
   * 图片裁剪通用接口
   */

  public static void cutImage(String src, String dest, int x, int y, int w,
      int h, String formatName) throws IOException
  {
    Iterator iterator = ImageIO.getImageReadersByFormatName(formatName);
    ImageReader reader = (ImageReader) iterator.next();
    InputStream in = new FileInputStream(src);
    ImageInputStream iis = ImageIO.createImageInputStream(in);
    reader.setInput(iis, true);
    ImageReadParam param = reader.getDefaultReadParam();
    Rectangle rect = new Rectangle(x, y, w, h);
    param.setSourceRegion(rect);
    BufferedImage bi = reader.read(0, param);
    ImageIO.write(bi, formatName, new File(dest));

  }

  /*
   * 图片缩放
   */
  public static void zoomImage(String src, String dest, int w, int h)
      throws Exception
  {
    double wr = 0, hr = 0;
    File srcFile = new File(src);
    File destFile = new File(dest);
    BufferedImage bufImg = ImageIO.read(srcFile);
    Image Itemp = bufImg.getScaledInstance(w, h, bufImg.SCALE_SMOOTH);
    wr = w * 1.0 / bufImg.getWidth();
    hr = h * 1.0 / bufImg.getHeight();
    AffineTransformOp ato = new AffineTransformOp(
        AffineTransform.getScaleInstance(wr, hr), null);
    Itemp = ato.filter(bufImg, null);
    try
    {
      ImageIO.write((BufferedImage) Itemp,
          dest.substring(dest.lastIndexOf(".") + 1), destFile);
    }
    catch (Exception ex)
    {
      ex.printStackTrace();
    }

  }
}
